help in beefing up the rear.

[Machuban1]

well like the title says. i am in need of help with beefin up my rear. i dont really no nothing about it. i wanted to get forged 28 spline axles but should i get these or should i go to 31 spline?? also i plan to have it in the 11's (not anytime soon lol) but want to get everything done now. would you guys recomend forged 28 spline or 31??

also when i change these out should i change the differential?? if so which one?

i want to put 4:10 gears too.

all help appreciated